Usually when a large meteor hits the Earth, it's a cataclysmic event that heralds the extinction of various species. But they also mean lots of diamonds. The latest cache of meteor-made diamonds was just discovered in California.

It is hard to explain this assemblage of materials without a cosmic impact event and associated extensive wildfires. This hypothesis fits with the abrupt climatic cooling as recorded in ocean-drilled sediments beneath the Santa Barbara Channel. The cooling resulted when dust from the high-pressure, high-temperature, multiple impacts was lofted into the atmosphere, causing a dramatic drop in solar radiation.

The diamonds, which are too tiny to use in jewelry, have only been found at other known cosmic hit sites, where they appear to be the result of impacts and the concomitant wildfires.